Process for obtaining light hydrocarbons from heavy hydrocarbons



F. BERGIUS.

PROCESS FOR OBTAINING LIGHT HYDROCARBONS FROM HEAVY HYDROCARBONS.

APPLICATION FILED FEB- IZ, I9I4.

1 ,344, 67' 1 Patented June 29, 1920.

UNITED STATES PATENT OFFICE.

FRIEDRICH BERGIUS, OF HANOVER, GERMANY, ASSIGNOR, BY MESNE ASSIGNMENTS, TO THE CHEMICAL FOUNDATION, INC, A CORPORATION OF DELAWARE.

PROCESS FOR OBTAINING LIGHT HYDROCARBONS FROM HEAVY HYDBOCAEBONS.

Specification of Letters Patent. Patented J 11119 29, 1920,

Application filed February 12, 1914. Serial No. 818,224.

taining Light Hydrocarbons from Heavy Hydrocarbons, of which the following is a specification.

Processes already exist by which light hydrocarbons such as henzin, gasoleneand the like are produced or split off from heavy" hydrocarbons, such as petroleum and the like, by heating. The yield of the lighter hydrocarbons, produced by these simple heating processes, is, however, comparatively small because of the large production of less readily condensed gases on the one hand and of carbonaceous residues on the other hand. Furthermore, because of the production of these less readily condensed gases, the lighter hydrocarbons obtained by these processes, generally known as cracking processes, are of inferior quality and have an objectionable smell, containing large amounts of unsaturated hydrocarbons; they are colored and deposit carbon when burned.

The object of the present invention is to avoid the disadvantages just mentioned by converting all unsaturated compounds produced into saturated compounds. This can be accomplished by adding hydrogen to the said unsaturated compounds. f hydrogenation has been attempted heretofore, it has not been altogether satisfactory and it is the purpose of the present invention to provide an improved method of hydrogenation which shall be free from disadvantages hitherto existent.

According to my invention, about to be described, I cause hydrogen to react with unsaturated hydrocarbons by bringing them together at a very high pressure and high temperature. Instead of pure hydrogen, mixtures of hydrogen with other gases, especially mixtures of hydrogen with neutral gases which do not react with the unsaturated hydrocarbons such as nitrogen,

methane and carbon monoxid, could be While such it must be remembered that the pressure of such mixed gases must be suitably higher in order that the partial pressure due to the hydrogen per se may have the desired value of at least 20 atmospheres. Motor spirits obtained in this manner differ from the usual products of cracking processes by being colorless, having very little smell, and burning at high efficiency without any substantial formation of soot. Chemical examination of the products shows that but a small percentage of unsaturated compounds is included in the same.

In carrying out my improved process, I heat heavy hydrocarbons as, for example, petroleum, its distillation products and residues, or heavy hydrocarbons obtained from bitumen and the like, in a rupture proof vessel in the presence of free or dissolved hydrogen and at'a pressure for the hydrogen ofat least 20 atmospheres; preferably I employ temperatures inexcess of 250 C.

for several hours. The product is then transferred to a distilling apparatus in which the light hydrocarbons which have been formed are distilled off and fractionated.. The remaining heavy residue can either be further treated in a second similar I operation, or used without further change as obtained from the decomposition of heavy hydrocarbons if, during the process of de composition, the production of gaseous products is held back as much as possible by the application of hi h pressure to said heavy hydrocarbons. he means for producing this pressure may act directly in the vessel containing the heavy hydrocarbons,

or in a vessel communicating with said first I named vessel. T he means may be mechanical, such as, for example, a piston placed under pressure; or it may be gaseous.

To effectually hold back the gaseous products and prevent their escape from the heavy hydrocarbons requires a pressure of at least 20 atmospheres and a pressure of 30 atmospheres is preferable. If a gas is used as the pressure medium and forced into the reaction chamber in a cold state, the pressure with which it is so forced in should be in excess of 15 atmospheres.

It has been found that the process just described makes it possible to simultaneously remove sulfur from the materials treated and to effect this removal in a quantitative manner by using metals, metal oxids or hydroxids as the desulfurizing means. In effecting the desulfurizing it is generally sufficient to have a temperature of 300 C. at a pressure of about 50 atmospheres, the heating varying from one half hour to two hours. The use of the mentioned desulfurizing means facilitates the reaction for converting heavy hydrocarbons into light hydrocarbons and shortens the time required for such reaction.

My improved process may be carried out with various types of apparatus. The accompanying drawings show, in a somewhat diagrammatic fashion, types of apparatus which I have found satisfactory. in these drawings, Figure 1 shows a construction of apparatus in which the pressure medium is applied in the reaction vessel itself; and Fig. 2 shows a construction in which the pressure medium is applied in a vessel which communicates with the reaction vessel.

In the drawing, 1 is the rupture proof reaction vessel into which the heavy hydrocarbons to be treated are introduced through a pipe 2 having a high pressure valve 3. A

pipe 4. leads to a tank 5 which contains hydrogen or a mixture of hydrogen and other gases as previously set forth under pressure which is used as a pressure medium; this pipe is provided with a high pressure valve 6 and a pressure gage 7. Pipe 2 projects but a short distance into the reaction vessel 1 and the pipe 4 preferably projects well below the surface of said hydrocarbons as indicated at 8; in this way, the hydrogen or hydrogen and other gas mixed which is admitted into the reaction vessel simultaneously stirs the heavy hydrocarbons and at the same time mixes with them. If the stirring of the hydrocarbons, produced by the gas, is not sufiicient for thorough mixing,

a stirring device (not shown) may also be.

employed. The temperature of the hydrocarbons is determined by a thermometer (not shown) inserted in the thermometer pipe 9.

I A pipe 10 with valve 11 arranged at aaaerr the bottom of the reaction vessel 1 for dis-' charging the products resulting from the reaction, which products are carried away for further treatment by distillation.

Referring to Fig. 2, the reaction vessel is designated by the numeral 12 and the liquid hydrocarbons are supplied to it. through a pipe 13 having a valve 14. In use, the reaction vessel is fairly completely filled with the liquid hydrocarbons, the remaining space being filled with hydrogen or with mixed gas containing hydrogen. Tank 12 is connected by pipe 15 to a vessel 16 partly filled with heavy'hydrocarbons. Pressure in the direction of arrow 17 is exerted on the surface of the liquid in tank 16 by means of a suitable piston l or by means of liquid hydrocarbons which are pumped into tank 16 at suitable pressure; or the surface-of the liquid in tank 16 may be acted upon by a suitable gas pressure. Pipe '18 serves to introduce the heavy hydrocarbons into tank 16.

In the constructions, both of Fig. l and Fig. 2, tanks 1 and 12 are respectively heated in any preferred manner as, for example, by furnace gases which may be caused to pass through the pipes F.

The following example is typical of the operation of my improved process.

Example: 10 kg. of Galician gas oil with. boiling point between 270 C. and 360 C. were placed in a rupture proof vessel. Hydrogen at a pressure of100 atmospheres was then pumped into the reaction vessel and the vessel tightly closed and heated to about 400 C. After 12 hours heating, the contents of the vessel, weighing 9.7 kg, were removed and fractionally distilled.

The quantities and weights of distillate 1 were obtained as follows Up to 60 C 1.2 kg. Between 60 C. and 120 C 1.5 kg. Between 120 C. and 150 0.9 kg. Between150 C. and 180 C 0.9 kg.- Between 180 C. and 250 C 1.9 kg. Between 250 C. and 300 C 1.2 kg. Between 300 C. and 360 1.8 kg. Over 360 C 0.3 kg.

The several distillates had very little odor,

carbons from heavy hydrocarbons which comprises heatingthe heavy hydrocarbons.

in contact with and under a pressure of hydrogen of about 100 atmospheres.

3. The process of obtaining light hydrocarbons from heavy hydrocarbons which comprises heating the heavy hydrocarbons in contact with and under a pressure of hydrogen exceeding 20 atmospheres, and maintaining the working temperature during the operation at about 400 C. and at not less than 250? C.

4. The process of obtaining light hydro- ,carbons from heavy hydrocarbons which 10 comprises heating the heavy hydrocarbons in contact with and under a pressure of hydrogen of about 100 atmospheres and maintaining the working temperature at about 400 (J. and not less than 250 C.

In testimony whereof I afiix my signature 15 in presence of two witnesses.

DR. FRIEDRICH BERGIUS. Witnesses:

HUGO Gnorrr,

T. HENRY REED. 

